The present invention relates generally to railway coupler connections and more particularly to an improved slackless coupler connection in which a vertically restrained coupler member is permitted to angle horizontally while the butt end of the coupler member is laterally and longitudinally restrained within the center sill by a self-adjusting follower member.
Railway cars are connected together by coupler members, namely drawbars or couplers. Drawbars are integral units known to be used in the railroad industry to extend between and permanently connect two or more railcars. Couplers are independent units on each car which interconnect with one another, between adjacent cars, to form a connection. In either instance, a shank and butt end of the drawbar or coupler extends into the center sill of a railway car where it is secured to transmit longitudinal loads to the car.
One problem which arises in coupler connections is excessive slack. Horizontal angling of the coupler member which occurs during the negotiation of curves cannot be accommodated by a coupler member with a square butt end unless there is slack between the butt end of the coupler member and a follower block which takes the buff load from the coupler member. However, excessive slack causes impact forces which can result in car instability and damage to the railway car and the lading thereon. Hence a slackless coupler connection between the coupler member and the center sill is desirable.
U.S. Pat. No. 4,700,853 discloses a coupler member which is positioned and held within the center sill of a railway car by the combination of a draft key assembly, follower block, tapered wedge and pocket casting, all of which longitudinally position the coupler member within the center sill and a pair of sill side castings which laterally position the coupler member within the center sill. A convex butt end of the coupler member fits against a concave matching face of the follower block. The tapered wedge drops to take up the slack which results. However, this arrangement requires multiple parts which adds weight as well as expense to the railcar.